Ground floor front, side and rear extension, garage conversion, façade alterations and paved driveway

Appeal Decision Site visit made on 10 October 2025 by P Barton BA (Hons) MA MRTPI an Inspector appointed by the Secretary of State Decision date: 3RD November 2025 Appeal Ref: 6000384 10 Derwent Drive, Petts Wood, Orpington, Bromley BR5 1EW • The appeal is made under section 78 of the Town and Country Planning Act 1990 (as amended) against a refusal to grant planning permission. • The appeal is made by Mr Basant Mertia against the decision of the Council of the London Borough of Bromley. • The application Ref is DC/25/00281/FULL6 • The development proposed is ground floor front, side and rear extension, garage conversion, façade alterations and paved driveway. Decision 1. The appeal is allowed and planning permission is granted for ground floor front, side and rear extension, garage conversion, façade alterations and paved driveway at 10 Derwent Drive, Petts Wood, Orpington, Bromley BR5 1EW, in accordance with the terms of the application, Ref DC/25/00281/FULL6, and the details submitted with it and subject to the following conditions: 1) The development hereby permitted shall begin not later than 3 years from the date of this decision. 2) The development hereby permitted shall be carried out in accordance with drawing nos. PN-104 Proposed Floor Plan, PN-105 Proposed Roof Plan, PN- 106 Proposed Elevations, PN-107 Proposed Elevations and PN-108 Block Plans. 3) The external materials of the extensions hereby permitted shall match those used in the existing building. Applications for costs 2. An application for costs was made by Mr Basant Mertia against the Council of the London Borough of Bromley. This application is the subject of a separate Decision. Preliminary Matters 3. I have amended the description in the banner header and my formal decision above from that given in the application form as this is a more concise description of the proposal and removes superfluous text. Main Issues 4. From a review of the reason for refusal in the Council’s decision and the officer report, it would appear that the Council has concerns regarding the roof design to the side and rear extension. No concerns are raised regarding the other aspects of Appeal Decision 6000384 2 the side and rear extension, the front extension, the garage conversion, façade alterations or paved driveway. I have determined the appeal on this basis. 5. Whilst not specifically referenced in the formal reason for refusal, the Council has indicated within the officer report that the proposed roof design of the side and rear extension would have a harmful effect on the living conditions of neighbouring occupiers. 6. Accordingly, the main issues are the effect of the proposed development on: • the character and appearance of the host building and the surrounding area; and • the living conditions of the occupiers of nearby properties, with particular reference to outlook. Reasons Character and appearance 7. 10 Derwent Drive is one of a pair of semi-detached bungalows set amongst similar style and age bungalows and 2-storey properties along Derwent Drive and Greenfield Gardens. Whilst I observed a wide variety of alterations to many of these properties in the form of front porches, garage conversions, side extensions, and dormers, there remained a strong degree of harmony between them that influenced the overall character and appearance of this suburban location. 8. The proposals would see a reconfiguration of the property and much of the appeal scheme would replace existing structures and a conservatory that have flat or very shallow roofs. 9. The hipped crown roof to the proposed extensions would be a departure from the immediately surrounding bungalows where existing extensions predominantly have flat roofs. However, the pitched elements of the roof design would respect the existing main pitched roofs that are a dominant feature in the street scene. Moreover, the flat sections of the roof design would reduce their height and give the extensions a subordinate appearance. It would also reflect a number of subordinate extensions with crown roofs to both bungalows and 2-storey properties a very short distance away along Derwent Drive and Greenfield Gardens. 10. For the above reasons, the proposed development would have an acceptable effect on the character and appearance of the host building and the surrounding area. It accords with Policies 6 and 37 of the London Borough of Bromley Local Plan (January 2019) (LBBLP), Policy D4 of the London Plan (March 2021) (LP) and the Council’s Urban Design Guide Supplementary Planning Document (July 2023). Together these policies require proposals to respect or complement those of the host dwelling and be compatible with development in the surrounding area. Living conditions 11. The pitched roof section adjacent to the boundary with 12 Derwent Drive would have a similar eaves height to the existing extension and conservatory in this location. As the roof would slope away from the boundary for a short distance before the flat roof section, the inclusion of this roof design would not result in an Appeal Decision 6000384 3 unacceptable adverse impact in terms of overshadowing and being overbearing on the occupiers of No. 12 compared to the existing situation. Due to the overall height of the roof design and the distance to other neighbouring properties, including a foot and cycle path between the appeal site and 8 Derwent Drive, I am not persuaded there would be any harm to any of the other neighbouring properties in this regard. 12. I therefore conclude that the proposal would have an acceptable effect on the living conditions of the occupiers of nearby properties, with particular regard to outlook. I find no conflict with Policy 37 of the LBBLP which, amongst other things, seeks proposals that respect the amenity of occupiers of neighbouring buildings. Other Matters 13. I note concerns raised relating to the provision of guttering on the extension and whether this would encroach onto neighbouring land as well as possible associated nuisance, maintenance and damage issues rainwater might cause if not suitably provided for. The appellant has emphasised that the drainage for the roof would be designed to ensure that all rainwater is effectively collected and managed within the boundaries of the site. The plans do not appear to show any guttering or downpipes. However, there are a variety of methods that rainwater can be adequately addressed on an extension, and I see no reason why this would not occur in this case. Moreover, matters of encroachment and damage are a private matter, as is the party wall notification, between the relevant parties and are not in my jurisdiction. 14. The Council did not raise any objections to the proposal in terms of drainage, including the use of permeable slabs to the paved driveway, which is shown on the proposed block plan. Based on the evidence before me I find no reason to disagree with the Council, and a planning condition is not necessary in this regard. Conditions 15. In addition to the standard time condition, I have imposed a condition requiring that the development is carried out in accordance with the approved plans, as this provides certainty. 16. A condition is also necessary for materials to match those used on the existing house to protect the character and appearance of the area. Conclusion 17. For the reasons given above, I conclude that the appeal should be allowed. P Barton INSPECTOR